US EPA

3296769 

Journal Article 

Assessing the soil erosion control service of ecosystems change in the Loess Plateau of China 

Fu, B; Liu, Yu; Lu, Y; He, C; Zeng, Y; Wu, B 

2011 

Yes 

Ecological Complexity
ISSN: 1476-945X 

ELSEVIER SCIENCE BV 

AMSTERDAM 

8 

4 

284-293 

10.1016/j.ecocom.2011.07.003 

WOS:000297874800002 

Soil erosion in terrestrial ecosystems, as an important
global environmental problem, significantly impacts on environmental quality and social economy.
By protecting soil from wind and water erosion, terrestrial ecosystems supply human beings with
soil erosion control service, one of the fundamental ecosystem services that ensure human
welfare. The Loess Plateau was one of the regions in the world that suffered from severe soil
erosion. In the past decades, restoration projects were implemented to improve soil erosion
control in the region. The Grain-to-Green project, converting slope croplands into forest or
grasslands, launched in 1999 was the most massive one. It is needed to assess the change of soil
erosion control service brought about by the project. This study evaluated the land cover changes
from 2000 to 2008 by satellite image interpretation. Universal Soil Loss Equation (USLE) was
employed for the soil erosion control assessment for the same period with localized parameters.
Soil retention calculated as potential soil erosion (erosion without vegetation cover) minus
actual soil erosion was applied as indicator for soil erosion control service. The results
indicate that ecosystem soil erosion control service has been improved from 2000 to 2008 as a
result of vegetation restoration. Average soil retention rate (the ratio of soil retention to
potential soil loss in percentage) was up to 63.3% during 2000-2008. Soil loss rate in 34% of the
entire plateau decreased, 48% unchanged and 18% slightly increased. Areas suffering from intense
erosion shrank and light erosion areas expanded. Zones with slope gradient of 8 degrees-35
degrees were the main contribution area of soil loss. On average, these zones produced 82% of the
total soil loss with 45.5% of the total area in the Loess Plateau. Correspondingly, soil erosion
control capacity was significantly improved in these zones. Soil loss rate decreased from 5000 t
km(-2) yr(-1) to 3600 t km(-2) yr(-1), 6900 t km(-2) yr(-1) to 4700 t km(-2) yr(-1), and 8500 t
km(-2) yr(-1) to 5500 t km(-2) yr(-1) in the zones with slope gradient of 8 degrees-15 degrees,
15 degrees-25 degrees, and 25 degrees-35 degrees respectively. However, the mean soil erosion
rate in areas with slope gradient over 8 degrees was still larger than 3600 t km(-2) yr(-1),
which is far beyond the tolerable erosion rate of 1000 t km(-2) yr(-1). Thus, soil erosion is
still one of the top environmental problems that need more ecological restoration efforts. (C)
2011 Elsevier B.V. All rights reserved. 

Ecosystem services; Soil erosion; Soil conservation; USLE; Loess Plateau